An improved burner and a method for combusting fuel in burners used in furnaces
such as those found in steam cracking. The burner includes a burner tube having
a longitudinal axis and having a downstream end and an upstream end for receiving
fuel gas and air, flue gas or mixtures thereof, a fuel orifice located adjacent
the upstream end of the burner tube, for introducing fuel gas into the burner tube,
a burner tip mounted on the downstream end of the burner tube and adjacent a first
opening in the furnace, the burner tip having a plurality of main ports substantially
aligned with said longitudinal axis of the burner tube, and a plurality of peripherally
arranged side ports and an peripheral tile which peripherally surrounds the burner
tip, leaving at least one gap between an outer periphery of the burner tip and
the peripheral tile, the at least one gap effective for providing a portion of
the air for combustion wherein the quantity of fuel gas discharged during combustion
from the peripherally arranged side ports does not exceed 15% of the total fuel
gas combusted. Reducing the quantity of the fuel gas discharged from the side ports
during burner operation is effective to reduce NOx emissions during
combustion over a similar burner utilizing a conventional burner tip design.
